Check out the open house with the Japans Jun Auto.
photographer: Henry k. Dekuyper
JUN is a family-owned company that's been around for 60 years. It's one of the oldest automotive parts companies in Japan and one of the very few that remains family-owned. JUN has always prided itself on doing something that nobody else does: developing quality aftermarket products. We've always been fans of JUN because of the rigorous testing each of their products undergoes before it reaches our hands. We know that their extensive research translates to the best possible product for our vehicles.
Having appreciated their products from afar as consumers, we jumped at the opportunity to meet with JUN representatives in Japan. We were honored to sit down with Ms. Tanaka, the granddaughter of JUN's founder, and Mr. Koyama, JUN's Managing Director of Auto Mechanics, at their company headquarters outside of Tokyo.
London-educated and accented Ms. Tanaka translated for us, giving us a rare glimpse into the inner workings of JUN and Mr. Koyama's take on our industry. We discovered Mr. Koyama has been with JUN for 25 years, working his way up from their street-tuning division and machine shop. Prior to JUN he worked at a Toyota dealership.
One of the first things we wanted to know about was the "Stream Z" 350Z. JUN built this for Option's Daijiro Inada, and it was entered into the Silver State event that takes place in Nevada each September. As a collaboration with several other companies, this Option/JUN vehicle was built on all-Japanese technology. Mr. Koyama feels this event is a difficult car race, because they test the car in Japan without the luxury of having long circuits similar to Nevada to tune on. He notes the difference in tires too, because the Silver State road is rough. Also, the Silver State course is 200 meters above sea level. This difference is yet another challenge when testing cars in Japan for Nevada's altitude, climate and geography.
Mr. Koyama hopes that JUN's project Stream Z 350Z turbo will compete with the new GTRs. In fact, their 350Z borrows the tranny from the GTR. When asked how much power it makes, Mr. Koyama shied away from giving us a horsepower number but told us that it did 330 kilometers per hour for ten runs consecutively on the oval track, and that it could have even gone faster if they had wanted to push it. It was from this project Z that they developed their 350Z camshaft and stroker kit lines.
In addition to producing these kits, JUN tackled the problem of the Nissan 350Z's tires that burst and lacked traction. To fix these issues, JUN created an Impreza-style wheel suspension system. They developed a one-off product in this case - something JUN often does for their customers. Try finding a company in the U.S. to do that for you!
Mr. Koyama feels that the 350Z is good for cruising on the highway, but needs work for street tuning. Ms. Tanaka and Mr. Koyama feel there are problems with the 350Z chassis, because the manufacturer wanted to use the same parts for a variety of models and now the 350Z chassis is left being too high. Since Nissan was looking for cross-performance for the 350Z line, they made the model look sportier than it is, Mr. Koyama and Ms. Tanaka maintain. "It's not a sports car, it's a sports-like car." They attribute these difficulties with the 350Z to the fact that it was designed during a time period when Nissan was in bad shape.
JUN has also addressed the problem with the Honda Integra (our Acura RSX) K20's cam timing. They found that limiting and setting the valve timing is difficult, and want to work out the bugs before releasing their product line. While some companies are selling ECUs with their camshafts to adjust for cam timing, JUN is not going this easy route. Instead, JUN is striving to find a camshaft that works without ECU tuning.